Unlike the recent clerical workers' strike that shut down 10 of 14 local terminals, the ports of Long Beach and Los Angeles may see a slight uptick in cargo volumes if a strike occurs at East Coast ports.

However, any impact will likely be minimal, said Sean Strawbridge, managing director of port operations for the Port of Long Beach.

"It takes about 30 days for the supply chain to shift, so any change that has to happen has already been made," Strawbridge said.

Any uptick in cargo would be seen in late December to early January, typically a slow period for the port, he said.

However, some companies are concerned about the impact of strikes on multiple coasts.

Ingrid Hirstin Lazcano, founder of the Los Angeles-based Andean Dream LCC, said a strike on the East and Gulf coasts could bankrupt her company, which sells soups, pasta and other products made from quinoa, a grain grown in the Bolivian Andes.

The company has two containers shipped monthly to both Los Angeles and Philadelphia, and Lazcano said she's still recovering from the eight-day strike of 450 clerical workers at the Los Angeles-Long Beach port complex, which ended Dec. 4.

"If the strike does happen, we will be paralyzed," she said. "We will not be able to fill orders."

The latest talks between shipping companies and dockworkers on the East Coast have reportedly broken down less than two weeks before the contract expires Dec. 29, leading to worries that a strike could lead to the closure of 15 ports from Massachusetts to Texas.

The longshoremen's union on the East Coast represents 14,500 workers at the 15 ports, which extend south from Boston and handle 95 percent of all containerized shipments from Maine to Texas, about 110 million tons' worth. The New York-New Jersey ports handle the most cargo on the East Coast, valued at $208 billion in 2011.

Various issues, including wages, are unresolved, but the sides couldn't agree on what's become the key sticking point - container royalties.

The sides have traded charges of inflexibility, though both also point to a history of cooperation since the last East Coast-wide strike in 1977. No one has ruled out renewing talks.

But with time so short, companies are pushing up shipment dates or finding alternative transportation, said Steve Lamar, executive vice president of the Washington-based American Apparel and Footwear Association.

They are already worried about restocking after the holidays, and some are still dealing with the effects of the West Coast shutdown and Superstorm Sandy, Lamar said.

"You've already got companies and ports and trade that have been battered by a couple of situations over the last couple of months, and we still have this uncertainty," he said.

In Philadelphia, port executive Robert Blackburn estimates a strike could affect 60 percent of the tonnage the port handles.

"Frankly, there's not a lot we can do except hope that cooler heads prevail and, if they don't, perhaps there will be intervention by the president," Blackburn said.

Karen Robes Meeks and the Associated Press contributed to this report.